The implied domain of the function with rule `f(x) = cos^(-1)(log_e(bx), b > 0)` is
- `(0, 1]`
- `[1, e]`
- `[1/b, e/b]`
- `[1/b, (e^pi)/b]`
- `[1/(be), e/b]`
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The implied domain of the function with rule `f(x) = cos^(-1)(log_e(bx), b > 0)` is
`E`
`f(x)\ text(is defined when)`
`-1 <= log_e(bx) <= 1`
`1/e <= bx <= e`
`1/(be) <= x <= e/b`
`=>\ E`
A function `f` has the rule `f(x) = |b cos^(−1)(x) - a|`, where `a > 0, b > 0` and `a < (bpi)/2`.
The range of `f` is
`B`
`text(Range:)\ \ cos^(−1)(x) = [0, pi]`
`text(Range:)\ \ b cos^(−1)(x) – a = [−a, bpi – a]`
`text(Given)\ \ 0 < a < (bpi)/2, text(Range) = [−a, bpi – a]`
`:.\ text(Range:)\ \ |b cos^(−1) (x) – a| = [0, bpi – a]`
`=>B`
The maximal domain and range of the function \(f(x)=a \cos ^{-1}(b x)+c\), where \(a\), \(b\) and \(c\) are real constants with \(a>0, b<0\) and \(c>0\), are respectively
\(D\)
| \(\text{Domain:}\) | \(-1 \leq b x \leq 1, \quad b<0\) |
| \(\dfrac{1}{b} \leq x \leq-\dfrac{1}{b}\) |
| \(\text{Range:}\) | \(0 \leq \cos ^{-1}(b x) \leq \pi\) |
| \(0 \leq a \cos ^{-1}(b x) \leq a \pi\) | |
| \(c \leq a \cos ^{-1}(b x)+c \leq a \pi+c\) |
\(\Rightarrow D\)
The implied domain of the function with rule `f(x) = b + cos^(−1)(ax)` where `a > 0` is
A. `(−pi/a,pi/a)`
B. `[−1,1]`
C. `[−pi/a,pi/a]`
D. `(−1/a,1/a)`
E. `[−1/a,1/a]`
`E`
`−1 <= ax <= 1,\ \ a > 0`
`−1/a <= x <= 1/a`
`=> E`
The domain and range of the function with rule `f(x) = arccos(2x - 1) + pi/2` are respectively
A. `[−2,0]` and `[0,pi]`
B. `[−2,0]` and `[pi/2,(3pi)/2]`
C. `[0,1]` and `[0,pi]`
D. `[0,1]` and `[pi/2,(3pi)/2]`
E. `[0,pi]` and `[0,1]`
`D`
`text(Domain:)`
`-1 <= 2x – 1 <= 1`
`0 <= 2x <= 2`
`0 <= x <= 1`
`text(Range:)`
`0 <= cos^(-1) (2x – 1) <= pi`
`pi/2 <= cos^(_1) (2x – 1) + pi/2 <= (3 pi)/2`
`=> D`
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a. `text(Maximal domain:)`
| `1-2x` | `∈ [−1, 1]` |
| `-2x` | `∈ [−2, 0]` |
| `x` | `∈ [0, 1]` |
`text(When)\ \ x = 0,\ \ y = cos^-1 1= 0;`
`text(When)\ \ x = 1,\ \ y = cos^-1 (-1)= pi`
`:.\ text(Range is)\ \ [0, pi]`
| b. |
c. `y = cos^-1 (1-2x),`
| `(dy)/(dx)` | `= (-1(-2))/sqrt(1-(1-2x)^2)` |
| `= 2/sqrt(1-(1-2x)^2)` |
`text(At)\ \ x = 1/4,`
| `m_T` | `= 2/sqrt(1-(1-1/2)^2)` |
| `=2/sqrt(3/4)` | |
| `= 4/sqrt 3` | |
| `= (4 sqrt 3)/3` |
The implied domain of `y = arccos ((x - a)/b)`, where `b > 0` is
A. `[-1, 1]`
B. `[a - b, a + b]`
C. `[a - 1, a + 1]`
D. `[a, a + b pi]`
E. `[-b, b]`
`B`
| `(x- a)/b` | `in [-1, 1]` |
| `x – a` | `in [-b, b]` |
| `x` | `in [a – b, a + b]` |
`=> B`
The implied domain of the function with rule `f(x) = (3x)/(pi/2 - arccos (2 - x))` is
A. `[1, 3]`
B. `[-1, 1]`
C. `[0, 1) uu (1, 2]`
D. `[-1, 0) uu (0, 1]`
E. `[1, 2) uu (2, 3]`
`E`
`-1 <= 2 -x <= 1`
`-3 <= – x <= – 1`
`3 >= x >= 1\ \ …\ (1)`
`(2):`
`pi/2 != cos^(-1) (2 – x)`
`0 != 2 – x`
`x != 2\ \ …\ (2)`
`(1) nn (2)`
`1 <= x <= 3 nn x != 2`
`:. x in [1, 2) uu (2, 3]`
`=> E`